Devices of various kinds are known in the art for adjusting the depth of penetration of a cutting or shaping tool. Examples of such devices are disclosed in Canadian patent 587,025 and U.S. Pat. Nos. 3,131,599; 3,274,889; 3,285,135; 4,156,990; 4,279,554; and 4,406,568. However, none of these prior art devices is suitable for use in connection with a precision shaping tool, such as a jewelry burring tool. A burring tool is used in the jewelry industry for various operations, including cutting channels for diamonds and other precious stones and setting grooves in prongs at a predetermined depth.
One of the problems associated with burring tool operations is the difficulty in achieving a uniform cutting depth. A high level of skill is required on the part of the operator and even then uniform cutting depth may not be achieved to the desired degree of precision.
There is therefore a need for an adjustable guide which is mountable on precision shaping tools, such as jewelry burring tools, for precisely adjusting the depth of penetration of the tool to a predetermined uniform depth.